Objective: Changes in the circulation and surface contour of the optic disc and surrounding structures are felt to precede glaucomatous visual loss in most cases. Our objective is to apply a new method for detecting these changes to the study of patients with ocular hypertension and glaucoma. Ocular hypertensive patients with apparently normal optic discs will be studied to determane whether their discs are changing, and whether any of the changes which are found are predictive of visual field loss. Patients with established glaucoma will be studied to determine whether control of their intraocular pressure has stopped the progression of the disease. Our approach is to contour and to measure the volume of the optic disc depression while simultaneously monitoring the blood circulation pattern with a new form of fluorescein angiography. Method: Our method for contouring the optc disc is to use a set of stripes as the illumination in a fluorescein angiogram, and to extract, in a simple automated way, the contour information from the course of the stripes as they follow the contours of the disc.